Every day in the production of power lines, power lines a day to more than 100,000 meters, 50,000 plugs, such a huge data, its production process must be very stable and mature. After continuous exploration and research and European VDE certification body, national standard CCC certification body, the United States UL certification body, British BS certification body, Australia SAA certification body…….. The recognition of the power cord plug has been mature, the following introduction:
1. Power cord drawn with copper and aluminum monofilament
Power line commonly used copper, aluminum rod, at room temperature, the application of wire drawing machine through one or several tensile mold holes, so that its section is reduced, the length of the increase, strength improvement. Wire drawing is the first process of each wire and cable company, the primary process parameter of wire drawing is the die technology.
2. Annealed single wire of power cord
When the copper and aluminum monofilaments are heated to a certain temperature, the toughness of the monofilaments is improved and the strength of the monofilaments is reduced by means of recrystallization, so as to meet the requirements of wire and cable for conductive core. The key of annealing process is the oxidation of copper wire.
3. Stranding of the conductor of a power cord
In order to improve the flexibility of the power cord, so as to facilitate the laying of the device, the conductive wire core accepts a plurality of single wire twisted. In terms of the stranded mode of the conductor core, it can be divided into regular stranded and irregular stranded. Irregular twisting is divided into bundle twisting, unison double twisting, extraordinary twisting, etc. In order to reduce the occupied area of the wire, reduce the geometric size of the power line, in the stranded conductor is also used in the compact way, so that the popular circle is changed into semicircle, fan, tile shape and compact circle. This conductor is primarily used in power lines.
4. Power line insulation extrusion
Plastic power line mainly uses extruded solid insulation layer, plastic insulation extrusion technology requirements:
4.1. Bias degree: the bias value of the extruded insulation thickness is the main mark of the performance of extrusion degree, most of the product structure size and its bias value have clear rules in the specification.
4.2. Lubrication: the outer surface of the extruded insulation layer shall be lubricated, and shall not present bad quality problems such as coarse appearance, burning and impurities
4.3. Density: the cross section of the extrusion insulation layer should be dense and robust, and there should be no visible pinholes and no bubbles.
5. Wiring of power cord
About the multi-core power cord in order to guarantee the forming degree, reduce the shape of the power cord, it is generally required to twist into a circle. The mechanism of stranding is similar to that of conductor stranding, because the stranding joint diameter is large and most of the stranding methods are used. Cable craft requirements: one is the root insulation core turn over and lead to cable bending; The second is to avoid the insulation layer is scratched.
A large part of the cable is also completed along with the other two processes: one is filling, ensuring that the cable is rounded and unchanged; One is binding, ensuring that the cable core is not lax.
6. Inner sheath of power cord
In order to maintain the insulating core is not sheathed, an insulating layer is required to be properly maintained. The inner sheathing can be divided into extruded inner sheathing (isolation sheath) and wrapped inner sheathing (cushion). The wrapping pad replaces the lashing tape and is carried out simultaneously with the cabling process.
7. Armoring the power cable
The underground power line can accept the inevitable positive pressure effect in the task, and the inner steel belt armored structure can be selected. The power line is laid in places with both positive pressure effect and tension effect (such as water, vertical shaft or soil with large drop difference), and the equipment should be equipped with internal steel wire armored structure.
8. Outer sheath of power cord
The outer sheath is the part of the structure that maintains the insulation layer of the power line to avoid the corrosion of the elements. The primary effect of the outer sheath is to improve the mechanical strength of the power line, prevent chemical erosion, moisture-proof, waterproof immersion, prevent the power line from burning and so on. According to the different requirements of the power line, the plastic sheathing should be directly extruded by the extruder.